She seems to be switching between caring and concern and being abusive. That can be very confusing to someone who has a trauma history, or is still in a traumatic situation. I really think she needs to be confronted with her behavior, and shown that it is not helping you, at least right now. From some of the other comments, it seems that she has been helpful in the past, butf that does not excuse her current behavior, and showing care after mocking and shouting (or even using a stern tone knowing you are already upset) doesn't excuse the behavior either. I wonder if you could have someone, like a mental health advocate, speak to her for you or go with you when you speak to her. My concern would be that bringing it up could only set her into the mocking and name calling again, which would only defeat the purpose.